The present invention relates to air/water mixers, and more particularly to methods and apparatus for converting a nonpulsating air/water mixer for a swimming pool, therapy tub, spa or the like to a pulsating mixer.
In spas, therapy tubs, swimming pools and similar apparatus, steady-stream jets of water are projected into the body of water contained in the spa, tub or pool to provide a type of hydromassage, enhanced relaxation and other therapeutic benefits. To increase the action, force and benefit of such jets, the water, before projection, is mixed with air by means of air/water mixers that commonly employ a venturi-type action. Through a forced water supply system feeding each of the mixers, an increased velocity water jet is projected into a mixing chamber within the mixer. The water jet provides an area of reduced pressure (i.e., a water venturi) that pulls air into the chamber through a passage that communicates with ambient atmosphere or a forced air supply system. The air entering the chamber mixes with the water and the resulting aerated water jet is discharged through a nozzle into (below the surface of) the body of water contained in the spa or pool tub.
In the past, to further enhance the therapeutic benefits of the described aeration system, various attempts have been made to cause a pulsation in the aerated jets entering the tub water. One approach has been to intermittently block the water flow to each of the mixers. In an existing system, this requires that the main water supply system be modified by cutting into its supply piping and installing one or more devices which alternately block and unblock such piping. Aside from the expense and inconvenience of this operation (both from an installation and maintenance standpoint), such often complex devices can cause abrupt pressure increases and noise, imposing severe strains on the system, whether they are installed on new or existing systems.
Another approach has been to intermittently interrupt the air flow to the mixers. This, too, often requires cutting into the main supply system and installing air control devices. Such devices generally additionally require external controlling mechanisms and have proven even less desirable than water flow controllers, being less efficient, more complex, and more costly.
A third approach has been to intermittently disable or attenuate the water venturi within each of the mixers. While this method has generally yielded the best performance of the three, its retrofit application is somewhat limited due to the varying internal configurations of air/water mixers of different manufacturers. Stated otherwise, a given venturi-disabling device is often compatible with only one manufacturer's mixer.
Accordingly, it is an object of the present invention to provide an apparatus and method for converting a conventional nonpulsating air/water mixer to a pulsating one that avoids or eliminates above-mentioned and other problems and limitations of prior devices and methods.